By the time this class of pilots is actually commanding aircraft we will have self driving cars that will make ground transportation much more feasible.
1500 miles in a car with a reclining seat I can sleep in while the car drives itself is preferable to that distance in an airplane.
That’s an interesting point. 9/11 upped the drive/fly distance from 4-5 hours to 6-7 hours for me. That could cause another significant increase. Plus you could have the car drive at night, and spend part of the day sightseeing along the way.